PROJECT SUMMARY/ABSTRACT The goal of this K08 proposal is to provide the candidate with a framework to develop a comprehensive research program as a surgeon scientist investigating multi-level, theory-based interventions to improve the timeliness, equity, and quality of head and neck cancer (HNC) care delivery. HNC is a disease with poor survival despite intense therapy with surgery, radiation, and chemotherapy. HNC is also a disease with significant racial disparities in mortality; African Americans (AAs) have a 51% relative decrease in survival compared to whites. Delays starting postoperative radiation therapy (PORT) after HNC surgery are a key driver of high mortality and racial disparities in survival and thus an appealing therapeutic target to address both issues. Delayed, non- guideline-adherent PORT initiation affects 56% of HNC patients, is 31% more common in AAs, associated with an 11% absolute decrease in 5-year survival, and a key contributor to racial differences in mortality. Although delivering timely PORT is of critical importance to prevent excess mortality and racial disparities in survival, effective interventions to improve the rate of timely, equitable PORT are lacking, in part due to the gap in our understanding of the relevant barriers in this population. In this proposal, the candidate will develop, pilot-test, and evaluate the preliminary clinical impact of NDURE (Navigation for Disparities and Untimely Radiation thErapy), a novel theory-based PN intervention to improve timely, equitable PORT in HNC patients. The research objective is to evaluate the preliminary clinical impact of NDURE on delays and racial disparities starting PORT among HNC patients. The central hypothesis is that NDURE will decrease PORT delays and racial disparities in delay by improving care coordination, self-efficacy, interpersonal support, and knowledge. Specific Aim 1 will identify the multi-level barriers that contribute to delays starting PORT after HNC surgery through key informant interviews with HNC patients and providers. Specific Aim 2 will assess the feasibility and acceptability of NDURE in a single-arm pilot study. Specific Aim 3 will test NDURE in a pilot randomized controlled trial (RCT) to evaluate its preliminary clinical impact on delays starting PORT among white and AA HNC patients. Ultimately, this research will have a large scientific impact by enhancing our conceptual understanding of timely, equitable multimodal HNC care delivery. It will have a significant clinical impact through the development of a scalable and practical intervention to decrease delays and racial disparities starting PORT, thereby improving survival for HNC patients and decreasing racial disparities in mortality. The training objective is to address the candidate?s scientific gaps in cancer health disparities, qualitative research, health systems and interventions research, and clinical trial design and analysis through mentored scientific training integrated and aligned with his research. Completion of the research and scientific training will position the candidate well to lead research investigating multi-level, theory-based interventions to improve the timeliness, equity, and quality of HNC care delivery.